✅ Available with pneumatic or electric actuators
✅ Pneumatic actuator with rolling diaphragm (max. air supply pressure: 6 bar)
✅ Electric actuator with handwheel, overheating protection, and enclosure rating IP67
✅ Various plug designs for accurate flow control, including noise-reducing perforated plugs
✅ Multiple stem sealing options, including PTFE, EPDM, and stainless steel bellows
✅ Available in nominal pressure ratings PN16, PN25, and PN40
✅ Leakage class IV – VI compliance (DIN EN 60534-4)
✅ Explosion-proof electric actuator versions available (ATEX-certified)
Technical Specifications
Valve Types & Configurations
- ARI-STEVI® 425 – Straight-through control valve with standard sealing options
- ARI-STEVI® 426 – Control valve with stainless steel bellows for high-temperature applications
Material Options
| Model | Nominal Pressure | Material | Nominal Diameter (DN) |
|---|---|---|---|
| 22.425 / 22.426 | PN16 | EN-JS1049 | DN300 |
| 34.425 / 34.426 | PN25 | 1.0619+N | DN300-500 |
| 35.425 / 35.426 | PN40 | 1.0619+N | DN300-500 |
Other materials and custom versions available upon request.
Stem Sealing Options
| Model | Standard Sealing | Optional Sealing |
|---|---|---|
| 425 (DN300-500) | PTFE-packing (-10°C to 250°C) | Pure graphite packing (-10°C to 450°C) |
| 425 (DN300-500) | EPDM sealing (-10°C to 150°C, suitable for water & steam up to 180°C) | -- |
| 426 (DN300-500) | Stainless steel bellows with graphite (-60°C to 450°C) | Stainless steel bellows with EPDM sealing (-60°C to 150°C, suitable for water & steam up to 180°C) |
Pressure & Temperature Ratings
| Material | PN Rating | Temperature Range | Max Operating Pressure |
|---|---|---|---|
| EN-JS1049 | PN16 | -10°C to 120°C | 16 bar |
| EN-JS1049 | PN16 | 150°C | 15.5 bar |
| EN-JS1049 | PN16 | 200°C | 14.7 bar |
| EN-JS1049 | PN16 | 250°C | 13.9 bar |
| 1.0619+N | PN25 | -60°C to 450°C | 25 bar |
| 1.0619+N | PN40 | -60°C to 450°C | 40 bar |
Plug Designs & Flow Performance
- V-port plug with metal seat (standard) – Leakage Class IV (DIN EN 60534-4)
- V-port plug with PTFE-soft seal (max 200°C) – Leakage Class VI
- Pressure-balanced plug with metal seat – Includes PTFE piston seal with stainless steel spring (max 200°C)
- Perforated plug for noise reduction (optional) – Ideal for gas and steam applications
Actuation Options
Pneumatic Actuator – ARI-DP 34 / 35
- Max Air Supply Pressure: 6 bar
- Spring-opening or spring-closing function
- Handwheel for manual operation available (optional)
Electric Actuator – AUMA SAR (MATIC)
- Protection Class: IP67
- Integrated torque and travel switches
- Handwheel for emergency operation
- Overheating protection as standard
- Explosion-proof version available upon request
- Motor voltage: 400V 50Hz 3-phase (other voltages available upon request)
